piclist 2004\06\25\100713a >
www.piclist.com/techref/index.htm?key=
BY : Russell McMahon email (remove spam text)

Various thoughts on this thread.

1.    The inter-star bending rod is subject to the "laws" of relativity and
will not allow peturbatuions greater than light speed to travel
along/through it. Alas.

2.    Look at waves hitting a beach or ripples hitting the edge of a pool
etc. If the wave front is slightly off square, watch what happens to the
contact point as the wave hits the edge or shore. Whiel nothing on the wave
moves faster than wave speed, the contact point is related to the arctan of
the contact angle. For very small angles, the contact point can travel at
speeds of 100's of kilometres per hour when the wave is travelling under 10
kph. Nothing physical is actually moving this fast but the motion can be
very clearly observed. (The cutting point on a pair of scissor blades does
the same thing but with a multiplier of only a few times).

Now take a light wave meeting a surface at a small angle ...  :-)

3.    Beyond monkeys and pictures on a screen there is the number of
locations in the universe. Space is quantised in units of Planck length (PL)
and time in Planck time (PT). The total possible number of locations in a
universe of dimension L (whatever that may actally mean) is about (L /
Planck_length)^3. While this number is large it is finite. Similarly you can
define all possible locations in space and time for a universe of age T by
(L / PL)^3 x (T/PT). The universe has a finite number of possible locations
in time and space ;-). Now set your monkeys to work to do something useful
with that.

4.    The two (arguably) major competing theories for the formation of the
universe are

i.    that it was creating by an external pre-existant entity (where eternal
and pre-existant are meaningless terms because neither time or space existed
prior to their existing :-) ) OR

ii That it was created out of nothing by nothing.

Both theories have their problems, but I find the second requires far more
faith to believe than the former :-)

5.    Did John Lennon drink coffee ?

6.    Nothing of Einstein's forbids travelling faster than light. Just AT
the speed of light. Hawkings has shown (and it may or may not be true) that,
even though NOTHING can escape from a black hole, BH's radiate because
particles can "tunnel" across the Shwarzchild radius / event horizon. (There
are other ways of looking at this feat but tunneling is as valid (or not) as
any.) Tunnel diodes also operate by quantum tunneling where an energy
barrier is passed through without being crossed over.

So, IF it is possible to tunnel the light speed energy barrier, all sorts of
interesting things happen. Energy gains a sqrt(-1) term whose significance
is as yet (and may always be) unknown. BUT Plotting 0.5 m x V^2 and allowing
for relativistic mass shows that energy required DECREASES past light speed
to a minimum about (AFAIR) 10 x light speed and then again increases towards
infinity. IF you can tunnel light speed there are TWO equal energy points
you can jump to. One is slightly above light speed and the other about 10 or
more times light speed. You can't get to either until you are travelling at
(AFAIR) about 0.9C and odds are that to tunnel you need your  "'ship" to be
at around 0.999C +, so we aren't going to see this any time soon.

But non zero-rest-mass particles MAY be able to be persuaded to play these
games.

Now, go and write that science fiction story ....

7.    Quantum Mechanics says (rightly or wrongly) that causality is broken
at the foundational level. If you build something on an insecure foundation
it is necessarily insecure. While you may be able to take many steps to
shore it up, the basis of causality is lost if the foundation is non causal.
But it still all seems to hang together and work very nicely anyway.
Interesting.

8.    There are ABOUT as many grains of sand on the beaches of earth as
there are stars in the universe (around 10^21 give or take).
But, Abraham knew that :-)

RM

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